In the Strength and Power Development program, when the prescribed loading for the Muscle Snatch says something like 65%x5, is that 65% of your 1RM snatch or 65% of your 1RM muscle snatch? Same question for the Snatch Push Press... are the loading percentages for your 1RM snatch or your 1RM snatch push press?

% is of muscle snatch. If you don't have a 1rm MS, just take it up to a heavy single on the first MS workout and use that number to calculate %s.

Snatch PP %s are of snatch PP, but you can base it off your snatch unless that's limited considerably by technique. In the latter case, you can do as I suggested for the MS, or you can simply feel it out and use the %s as a guide to how much effort should be required and then use the increases as a guide.